Density fields for branched cytoskeletal networks in confined regions*

We model the structure of branching networks of living cell cytoskeletal filaments when these are rigidly contained with regions. Based on a grand canonical formalism, we present a formalism that allows the calculation of density and orientational density for filaments and branch points. The resulting nonlinear integral equations for quantities related to these densities are solved numerically. We find distinct local orientation, order parameter and density profiles for filament segments, as the degree of branching and the ratio of persistence lengths of the filaments to the confining region size are varied. Computational results for persistence lengths mimicking actin filament branching through the Arp2/3 complex will be presented.